Satraplatin pivotal phase III trial fails to meet primary endpoint

BOULDER, Colorado—The randomized, double-blind satraplatin phase III registration trial (SPARC) has failed to meet its primary endpoint of overall survival in patients with hormone-refractory prostate cancer, Pharmion Corporation and GPC Biotech AG said in a news release.

Earlier this year, FDA's Oncologic Drug Advisory Committee recommended that FDA delay approval of satraplatin until the SPARC data on overall survival were available. The findings will also impact the satraplatin submission to the European Medicines Agency (EMEA).

Based on the results, GPC Biotech is reevaluating its development plans for satraplatin, including the SPERA (Satraplatin Expanded Rapid Access) protocol in the United States.

"We are extremely disappointed with the findings," said Bernd R. Seizinger, MD, PhD, chief executive officer of GPC Biotech. "We are currently discussing with our partners, Pharmion and Yakult, plans for the future development of satraplatin."

The trial evaluated satraplatin plus prednisone vs placebo plus prednisone as a second-line treatment in 950 patients with hormone-refractory prostate cancer. The median overall survival was 61.3 weeks for the satraplatin arm vs 61.4 weeks for controls (HR 0.97, P = 80).

The sponsoring companies are currently conducting prespecified subset analyses of the study findings. "The key for our European submission now will be the prespecificed subset analyses and particular to focus on the impact of prior Taxotere [docetaxel] use, which we know is very important to the EMEA," said Patrick J. Mahaffy, president and CEO of Pharmion Corporation.